Thanks a ton, Pinion. I've been getting told by shops all over town that a 28 spline axle is a 28 spline axle, and for the most part they just wouldn't believe that it had to do with the splines. I don't know how much is cobbled together on the rear. The ring gear has "GMC" stamped on it. That normal? I haven't checked the ujoint hardware yet since it is at my shop instead of at home, but I'll take a look and report back on that. Here's a few pictures of it that I took the first time I tore it apart.
Photos of Axle
thanks again for the great explination